New research shows sense of smell can predict Alzheimer’s disease

Modern medicine has explored a multitude of avenues for detecting Alzheimer’s disease early on, from brain scans to blood tests. Now, researchers are looking to a part of the body that few would expect could help catch the form of dementia before it sets in: the nose.

The research behind the diagnostic method

At the July 2014 Alzheimer’s Association International Conference, which took place in Copenhagen, Denmark, scientists presented research that shows the capacity to detect risk with the Alzheimer’s smell test. During two different studies, researchers found that participants who were unable to detect specific odors had a higher risk of experiencing cognitive impairment related to Alzheimer’s. Scientists believe that, during early stages of dementia, the cells in the brain responsible for olfactory function are killed off. In fact, these cells, located in the first cranial nerve, are generally the first to be affected by Alzheimer’s.

What the findings mean for Alzheimer’s patients

As there is no cure for Alzheimer’s, the Alzheimer’s smell test does little for those who have already begun experiencing memory loss, confusion and other symptoms of Alzheimer’s disease. However, it could mean great benefits for future generations at risk of the cognitive condition due to genetics or other factors. It’s low-tech and less invasive than other methods being used today, such as testing for beta-amyloid and tau levels in the cerebrospinal fluid. A doctor who recognizes that someone has a faltering sense of smell can order more extensive screening for dementia, such as a brain positron emission tomography scan, which is essential for prevention and early intervention to slow the progression of the condition.

In an Alzheimer’s Association press statement, the organization also highlighted the economical effects of testing using sense of smell. With the number of Alzheimer’s patients expected to triple to 115 million by 2050, according to estimates by Alzheimer’s Disease International, there’s a dire need for quicker, more cost-effective diagnostic tools to meet that growing demand.

“In the face of the growing worldwide Alzheimer’s disease epidemic, there is a pressing need for simple, less invasive diagnostic tests that will identify the risk of Alzheimer’s much earlier in the disease process,” Dr. Heather Snyder, director of medical and scientific operations at the Alzheimer’s Association, said in a statement. “This is especially true as Alzheimer’s researchers move treatment and prevention trials earlier in the course of the disease.”